package com.pj.current.config;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import org.springframework.boot.autoconfigure.AutoConfigureAfter;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceAutoConfigure;
import com.alibaba.druid.spring.boot.autoconfigure.properties.DruidStatProperties;
import com.alibaba.druid.util.Utils;

/**
 * 类名称:RemoveDruidAdConfig 类描述: 去除druid底部的广告配置类 
 */
@Configuration
@ConditionalOnWebApplication
@AutoConfigureAfter(DruidDataSourceAutoConfigure.class)
@ConditionalOnProperty(name = "spring.datasource.druid.stat-view-servlet.enabled", havingValue = "true", matchIfMissing = true)
public class RemoveDruidAdConfig {

	/**
	 * 方法名: removeDruidAdFilterRegistrationBean 方法描述: 除去页面底部的广告 @param
	 * properties @return
	 * org.springframework.boot.web.servlet.FilterRegistrationBean @throws
	 */
	@SuppressWarnings({ "rawtypes", "unchecked" })
	@Bean
	public FilterRegistrationBean removeDruidAdFilterRegistrationBean(DruidStatProperties properties) {
		// 获取web监控页面的参数
		DruidStatProperties.StatViewServlet config = properties.getStatViewServlet();
		// 提取common.js的配置路径
		String pattern = config.getUrlPattern() != null ? config.getUrlPattern() : "/druid/*";
		String commonJsPattern = pattern.replaceAll("\\*", "js/common.js");

		final String filePath = "support/http/resources/js/common.js";

		// 创建filter进行过滤
		Filter filter = new Filter() {
			@Override
			public void init(FilterConfig filterConfig) throws ServletException {
			}

			@Override
			public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
					throws IOException, ServletException {
				chain.doFilter(request, response);
				// 重置缓冲区，响应头不会被重置
				response.resetBuffer();
				// 获取common.js
				String text = Utils.readFromResource(filePath);
				// 正则替换banner, 除去底部的广告信息
				text = text.replaceAll("<a.*?banner\"></a><br/>", "");
				text = text.replaceAll("powered.*?shrek.wang</a>", "");
				response.getWriter().write(text);
			}

			@Override
			public void destroy() {
			}
		};
		FilterRegistrationBean registrationBean = new FilterRegistrationBean();
		registrationBean.setFilter(filter);
		registrationBean.addUrlPatterns(commonJsPattern);
		return registrationBean;
	}
}
